A prequel to the best-selling God of War, forthcoming Portable PlayStation game God of War: Chains of Olympus, has now slipped back to 2008.

Sony was hoping the game would help sales of its Portable PlayStation console during the crucial Christmas period following impressive sales on the PlayStation 2, but development problems appear to have led to the delay.

Publisher Sony has confirmed the PSP game will now be released in the US March 4, but for the UK they will only commit to an 'early 2008' release date.

PSP users who signed up for a demo of the title will be given a special edition 'teaser' UMD before the full game is released, according to a Gamespot report.